Predictive energy equations for spinal muscular atrophy type I children

Abstract

Background Knowledge on resting energy expenditure (REE) in spinal muscular atrophy type I (SMAI) is still limited. The lack of a population-specific REE equation has led to poor nutritional support and impairment of nutritional status. Objective To identify the best predictors of measured REE (mREE) among simple bedside parameters, to include these predictors in population-specific equations, and to compare such models with the common predictive equations. Methods Demographic, clinical, anthropometric, and treatment variables were examined as potential predictors of mREE by indirect calorimetry (IC) in 122 SMAI children consecutively enrolled in an ongoing longitudinal observational study. Parameters predicting REE were identified, and prespecified linear regression models adjusted for nusinersen treatment (discrete: 0 = no; 1 = yes) were used to develop predictive equations, separately in spontaneously breathing and mechanically ventilated patients. Results In naïve patients, the median (25th, 75th percentile) mREE was 480 (412, 575) compared with 394 (281, 554) kcal/d in spontaneously breathing and mechanically ventilated patients, respectively (P = 0.009). In nusinersen-treated patients, the median (25th, 75th percentile) mREE was 609 (592, 702) compared with 639 (479, 723) kcal/d in spontaneously breathing and mechanically ventilated patients, respectively (P = 0.949). Both in spontaneously breathing and mechanically ventilated patients, the best prediction of REE was obtained from 3 models, all using as predictors: 1 body size related measurement and nusinersen treatment status. Nusinersen treatment was correlated with higher REE both in spontaneously breathing and mechanically ventilated patients. The population-specific equations showed a lower interindividual variability of the bias than the other equation tested, however, they showed a high root mean squared error. Conclusions We demonstrated that ventilatory status, nusinersen treatment, demographic, and anthropometric characteristics determine energy requirements in SMAI. Our SMAI-specific equations include variables available in clinical practice and were generally more accurate than previously published equations. At the individual level, however, IC is strongly recommended for assessing energy requirements. Further research is needed to externally validate these predictive equations.

Metabolic Dysfunction in Spinal Muscular Atrophy

“…Thus, patients who are reported as being underfed may in fact have not been, leading to overfeeding and consequences such as increased FM and worsening conditions [ 54 ]. Considering clinical features (ventilatory status and nusinersen treatment), a recent study put forward new energy equations to predict energy expenditure for SMA type I patients in the hope of circumventing these issues [ 61 ]. However, the authors still recommend indirect calorimetry to ensure better individualized support [ 61 ].…”

“…Considering clinical features (ventilatory status and nusinersen treatment), a recent study put forward new energy equations to predict energy expenditure for SMA type I patients in the hope of circumventing these issues [ 61 ]. However, the authors still recommend indirect calorimetry to ensure better individualized support [ 61 ]. A more detailed analysis of some of these studies has recently been published [ 62 ].…”

Nutritional, Gastrointestinal and Endo-Metabolic Challenges in the Management of Children with Spinal Muscular Atrophy Type 1

“…Many studies have reported various forms of undernutrition and overnutrition in SMA patients, suggesting a multifactorial impairment that can produce different nutritional phenotypes [ 25 , 26 ]. For this reason, energy needs should be properly evaluated in each patient.…”

“…Bertoli et al have shown that the thoracic-abdominal movements of SMA patients during spontaneous breathing, compared to the reduced ones of mechanical ventilation assisted patients, can significantly increase the resting energy expenditure (REE). Indeed, in this study, authors observed that the use of mechanical ventilation has led to a reduction in REE that reaches the 50% [ 25 ].…”

“…The International Standards of Care for SMA recommend an estimated amount of 9–11 kcal per cm [ 25 ]. An accurate estimation of REE in SMA patients must consider demographic variables (age, sex), anthropometric measurements (body weight, supine length, tibia length, body mass index), respiratory function (spontaneous, non-invasive ventilation, invasive ventilation / tracheostomy), type of nutrition (oral, nasogastric tube, gastrostomy) and a possible therapy with nusinersen.…”